Thin touch panel

ABSTRACT

A thin touch panel includes a transparent substrate with a black bordering around the inner surface of the transparent substrate. A plurality of metal connecting structures, metal guiding lines, transparent insulating structures and a transparent sensing layer are formed on the inner surface, so that the transparent substrate not only provides a touch surface, but also has the touch sensing ability, to decrease the manufacture material and increase the transmittance of the touch panel. Besides, the manufacture of the thin touch panel may not use any optical adhesive to decrease the manufacture cost and improve the yield. Further, the thin touch panel may satisfy the trend of thin design.

FIELD OF THE INVENTION

The present invention generally relates to a capacitive touch panel, andmore particularly to a thin touch panel.

DESCRIPTION OF THE RELATED ART

Most of the existing electronic products such as handheld computer,personal digital assistant (PDA), and information appliance (IA) may beequipped with a touch display screen 10 as illustrated in FIG. 1. Thetouch display screen 10 mainly comprises a capacitive touch module 12and a display panel 14. The conventional capacitive touch module 12comprises a capacitive touch panel 16 and a cover lens 18. A top surface181 of the cover lens 18 is capable of being a finger touch region. Ablack pattern 20 is formed on edges of a bottom surface 182 of the coverlens 18, and the black pattern 20 is tightly combined with a glasssubstrate 161 of the capacitive touch panel 16 by sticking an opticaladhesive 22. A sensing circuit layer 162 consisted of a transparentconductive film 163 such as indium tin oxide (ITO), an insulating layer164 and metal lines 165 is formed on a bottom surface of the glasssubstrate 161, which may detect capacitance variations and inducedcurrents caused of the sensing circuit layer 162 being touched, so as tofurther calculate a coordinate of a position being touched. In addition,a transparent over coat 24 is formed under the sensing circuit layer 162to protect the sensing circuit layer 162 from being scraped.

However, the cover lens 18 and the glass substrate 161 of the capacitivetouch panel 16 mentioned above are both made of glass. Thus, morematerials may be consumed during manufacturing. In addition, theconventional capacitive touch panel 16 and cover lens 18 aremanufactured respectively first and then unitized by stacked up insequence. However, the assembling process not only more complicated andspends much time, but also increases the total height of the capacitivetouch module 12, thus unable to confirm lighter and thinner requirementof the existing electronic products. Furthermore, since the opticaladhesive 22 is much expensive and hard to be stuck well, all the opticaladhesive 22, the capacitive touch panel 16 and cover lens 18 have to bediscarded because of unable to be reworked. Thus, these materials arewasted.

SUMMARY OF THE INVENTION

The present invention is directed to a thin touch panel, wherein a blackbordering, a transparent sensing layer, a plurality of metal connectingstructures, a plurality of metal guiding lines and a plurality oftransparent insulators are formed on an inner surface of a transparentsubstrate directly. Thus, the transparent substrate may not only be atouch end, but also have a touch control ability of thin touch paneldirectly. Comparing to the conventional touch panel, the glass substrateof the touch panel disposed between the cover lens and the display panelmay be simplified, so as to reduce material consumption and increase atransparency of the touch panel. In addition, the process of stickingthe cover lens and the glass substrate by using the optical adhesive maybe left out, so as to further reduce the cost of the sticking processand enhance the yield rate. Furthermore, the thickness of the wholestructure of the touch panel is reduced, so as to benefit a designtendency of thinning out the product.

According to an embodiment of the present invention, the thin touchpanel comprises a transparent substrate having an outer surface (anupper side of the substrate) and an inner surface (a lower side of thesubstrate) opposite to one another, the outer surface capable of being atouch end; a black bordering formed on edges of the inner surface (lowerside of the substrate) to dispose around a sensing region; a pluralityof metal connecting structures arranged as an array and formed on thesensing region, and a plurality of metal guiding lines formed on asurface of the black bordering; a plurality of transparent insulatorsrespectively corresponding to each of the metal connecting structuresand respectively covering part of the metal connecting structures, andtwo opposite ends of the metal connecting structures being exposed; atransparent sensing layer comprising a plurality of first sensing padsarranged on the sensing region as an array, a plurality of transparentconductive connecting structures disposed across surfaces of thetransparent insulators to electrically connect the first sensing padsand part of the metal guiding lines along a first direction, a pluralityof second sensing pads arranged on the sensing region as an array, andthe second sensing pads and part of the metal guiding lines beingelectrically connected along a second direction by the exposed oppositeends of the metal connecting structures (the second direction isdifferent to the first direction); and a transparent over coat coveringthe transparent sensing layer, the transparent insulators, the metalconnecting structures and the metal guiding lines.

According to another embodiment of the present invention, the thin touchpanel comprises a transparent substrate having an outer surface (anupper side of the substrate) and an inner surface (a lower side of thesubstrate) opposite to one another, the outer surface capable of being atouch end; a black bordering formed on edges of the inner surface (lowerside of the substrate) to dispose around a sensing region; a transparentsensing layer comprising a plurality of first sensing pads and aplurality of transparent conductive connecting structures formed on thesensing region of the inner surface, and the transparent conductiveconnecting structures electrically connecting the first sensing padsalong a first direction, a plurality of second sensing pads formed onthe sensing region adjacent to and isolated from one another andalternately arranged with the first sensing pads, and a plurality oftransparent guiding lines formed on a surface of the black bordering,and electrically connected to part of the first sensing pads and part ofthe second sensing pads; a plurality of transparent insulatorsrespectively covering each corresponding transparent conductiveconnecting structure, and each transparent insulator crossing on twoadjacent ends of two isolated second sensing pads; a plurality of metalconnecting structures respectively formed on each transparent insulator,and electrically connecting the second sensing pads along a seconddirection (the second direction is different to the first direction); aplurality of metal guiding lines formed on the transparent guidinglines; and a transparent over coat covering the transparent sensinglayer, the transparent insulators, the metal connecting structures andthe metal guiding lines.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a cross-sectional view of a conventional touch panel.

FIG. 2A illustrates a top view of a thin touch panel formed with a blackbordering according to an embodiment of the present invention.

FIG. 2B illustrates a top view of a thin touch panel formed with a blackbordering, metal connecting structures and metal guiding lines accordingto an embodiment of the present invention.

FIG. 2C illustrates a top view of a thin touch panel formed with a blackbordering, metal connecting structures, metal guiding lines andtransparent insulators according to an embodiment of the presentinvention.

FIG. 2D illustrates a top view of a thin touch panel formed with a blackbordering, metal connecting structures, metal guiding lines, transparentinsulators and a transparent sensing layer according to an embodiment ofthe present invention.

FIG. 2E illustrates a top view of a thin touch panel formed with a blackbordering, metal connecting structures, metal guiding lines, transparentinsulators, a transparent sensing layer and a transparent over coataccording to an embodiment of the present invention.

FIG. 2F illustrates a cross-sectional view of the FIG. 2E along the lineF-F′.

FIG. 2G illustrates an applied example of a thin touch panel.

FIG. 3A illustrates a top view of a thin touch panel formed with a blackbordering according to another embodiment of the present invention.

FIG. 3B illustrates a top view of a thin touch panel formed with a blackbordering and a transparent sensing layer according to anotherembodiment of the present invention.

FIG. 3C illustrates a top view of a thin touch panel formed with a blackbordering, a transparent sensing layer and transparent insulatorsaccording to another embodiment of the present invention.

FIG. 3D illustrates a top view of a thin touch panel formed with a blackbordering, a transparent sensing layer, transparent insulators, metalconnecting structures and metal guiding lines according to anotherembodiment of the present invention.

FIG. 3E illustrates a top view of a thin touch panel formed with a blackbordering, a transparent sensing layer, transparent insulators, metalconnecting structures, metal guiding lines and a transparent over coataccording to another embodiment of the present invention.

FIG. 3F illustrates a cross-sectional view of the FIG. 3E along the lineF-F′.

FIG. 3G illustrates an applied example of a thin touch panel.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to specific embodiments of thepresent invention. Examples of these embodiments are illustrated in theaccompanying drawings. While the invention will be described inconjunction with these specific embodiments, it will be understood thatit is not intended to limit the invention to these embodiments. In fact,it is intended to cover alternatives, modifications, and equivalents asmay be included within the spirit and scope of the invention as definedby the appended claims. In the following description, numerous specificdetails are set forth in order to provide a through understanding of thepresent invention. The present invention may be practiced without someor all of these specific details. In other instances, well-known processoperations are not described in detail in order not to obscure thepresent invention.

Referring to FIG. 2A, a thin touch panel comprises a transparentsubstrate 32 having an outer surface (not shown) and an inner surface321 opposite to one another. The outer surface is capable of being atouch end. The inner surface 321 is designed with a sensing region 34,and a black bordering 36 are formed on edges of the inner surface 321 todispose around the sensing region 34. In an embodiment, the transparentsubstrate 32 may be a transparent insulating board or a transparentinsulating flexible board with a material of glass, polycarbonate (PC),polythylene terephthalate (PET), polymethylmethacrylate (PMMA), cyclicolefin copolymer (COC) or polyether sulfone (PES). However, the materialof the transparent substrate 32 of the present invention is not limitedto the previous materials. In addition, the black bordering 36 may be ablack array pattern made of chromium (Cr), chromium oxide or resin.

In addition, referring to FIG. 2B, a plurality of metal connectingstructures 38 are arranged as an array and formed on the sensing region34 of the inner surface 321, and a plurality of metal guiding lines 40are formed on a surface of the black bordering 36. In an embodiment, themetal connecting structures 38 and the metal guiding lines 40 are formedon the sensing region 34 and on the black bordering 36 respectively byforming one or a stack of metal material layer(s) with a conventionalmethod, such as, but not limited to, sputtering deposition method,wherein the metal material comprises at least one of, but not limitedto, silver (Ag), chromium (Cr), aluminum (Al) or amolybdenum/aluminum/molybdenum (Mo/Al/Mo) stack layer.

Then referring to FIG. 2C, a plurality of transparent insulators 42 arerespectively corresponding to each metal connecting structures 38, andrespectively crosses and covers a center part of each metal connectingstructures 38, thus only two opposite ends of each metal connectingstructures 38 are exposed. In an embodiment, the transparent insulators42 are formed from a photosensitive transparent insulating layer madeof, such as, but not limited to, ink or PET with high transparency afterexposure and development processes.

Further, referring to FIG. 2D, a transparent sensing layer 44 isdisposed on the inner surface 321. The transparent sensing layer 44comprises a plurality of first sensing pads 441, a plurality oftransparent conductive connecting structures 442, a plurality of secondsensing pads 443 and a plurality of transparent guiding lines 444. Thefirst sensing pads 441 and the second sensing pads 443 are arrangedalternately, and the second sensing pads 443 are disposed adjacent toand isolated from one another on the inner surface 321 of the sensingregion 34. The transparent conductive connecting structures 442 arerespectively disposed across and covering surfaces of each transparentinsulator 42 to electrically connect the first sensing pads 441 along afirst direction X, and every two adjacent and isolated second sensingpads 443 are electrically connected by the exposed opposite ends of eachmetal connecting structures 38 respectively along a second direction Y(the second direction Y is different to the first direction X). Inaddition, a plurality of transparent guiding lines 444 covercorresponding surfaces of the metal guiding lines 40 (as illustrated inFIG. 2B). One end of each transparent guiding line 444 is electricallyconnected with a first sensing pad 441 or a second sensing pad 443adjacent to the edges of the sensing region 34, and the other end ofeach transparent guiding line 444 is electrically connected with asignal output flat cable or a conductive circuit (not shown).

In an embodiment, the first sensing pads 441 and the second sensing pads443 are formed as rhombus shapes or polygon shapes, and sizes thereofare all the same or similar to one another. In addition, the transparentconductive connecting structures 442 are formed as strip shapes, therebyelectrically connecting and tightly arranging the first sensing pads441. The transparent sensing layer 44 is formed from a transparentphotosensitive conductive material, such as indium tin oxide (ITO),indium zinc oxide (IZO), antimony tin oxide (ATO), aluminum zinc oxide(AZO), zinc oxide (ZnO), tin oxide (SnO₂) or organic transparentconductive material. In addition, the first sensing pads 441, thetransparent conductive connecting structures 442, the second sensingpads 443 and the transparent guiding lines 444 are formed by processinga photolithography process on the same transparent photosensitiveconductive material.

Then referring to FIGS. 2E and 2F, wherein the FIG. 2F illustrates across-sectional view of the FIG. 2E along the line F-F′. A thin touchpanel 30 may further comprise a transparent over coat 46 covering thetransparent sensing layer 44, the transparent insulators 42, the metalconnecting structures 38 and the metal guiding lines 40 mentioned aboveand only conductive pads 48 for electrically connecting outside areexposed, so as to protect the above-mentioned structure from beingscraped except conductive pads 48. In an embodiment, the transparentover coat 46 is formed from an insulating material, such as, but notlimited to, silicon oxide (SiO₂).

Still referring to FIG. 2F, wherein a black bordering 36, metalconnecting structures 38, metal guiding lines 40, transparent insulators42 and a transparent sensing layer 44 are formed on the inner surface321 of the transparent substrate 32. The metal guiding lines 40 andtransparent guiding lines 444 of the transparent sensing layer 44 areformed on the black bordering 36, thereby being covered by the blackbordering 36 and not exposed outside the transparent substrate 32, so asto have artistic, orderly and integral effects. As an applied exampleillustrated in FIG. 2G, a thin touch panel 30 of the present inventionmay be disposed on a display panel 50 to form a thin touch displayscreen 60.

The present invention may further be formed by using another process.Referring to FIG. 3A, a thin touch panel comprises a transparentsubstrate 32 having an outer surface (not shown) and an inner surface321 opposite to one another. The outer surface is capable of being atouch end. The inner surface 321 is designed with a sensing region 34,and a black bordering 36 are formed on edges of the inner surface 321 todispose around the sensing region 34. In an embodiment, the transparentsubstrate 32 may be a transparent insulating board or a transparentinsulating flexible board, and the black bordering 36 may be a blackarray pattern. The materials have been illustrated in the previousembodiment and are omitted herein.

Further, referring to FIG. 3B, a transparent sensing layer 44 isdisposed on an inner surface 321 of the transparent substrate 32. Thetransparent sensing layer 44 comprises a plurality of first sensing pads441, a plurality of transparent conductive connecting structures 442, aplurality of second sensing pads 443 and a plurality of transparentguiding lines 444. The transparent conductive connecting structures 442herein electrically connect the first sensing pads 441 along a firstdirection X, and the second sensing pads 443 are adjacent to andisolated from one another and alternately arranged with the firstsensing pads 441. In addition, the transparent guiding lines 444 areformed on the black bordering 36 over the inner surface 321, and part ofthe transparent guiding lines 444 are electrically connected to thefirst sensing pads 441 adjacent to the edges of the sensing region 34,and another part of the transparent guiding lines 444 are electricallyconnected to the second sensing pads 443 adjacent to the edges of thesensing region 34. The other end of each transparent guiding line 444 iselectrically connected with a signal output flat cable or a conductivecircuit (not shown). Similarly, the shapes, the materials and theprocesses of the first sensing pads 441, the second sensing pads 443,the transparent conductive connecting structures 442 and the transparentguiding lines 444 have been illustrated in the previous embodiment andare omitted herein.

Then referring to FIG. 3C, a plurality of transparent insulators 42 arerespectively corresponding to and covers on each transparent conductiveconnecting structures 442, and respectively crossing on two adjacentends of two isolated second sensing pads 443. The material and theprocess of the transparent insulators 42 have been illustrated in theprevious embodiment and are omitted herein.

In addition, referring to FIG. 3D, a plurality of metal connectingstructures 38 are arranged as an array and respectively formed on asurface of each transparent insulators 42 to electrically connect everytwo adjacent and isolated second sensing pads 443 along a seconddirection Y (the second direction is different to the first direction),and a plurality of metal guiding lines 40 are formed on the transparentguiding lines 444. The metal materials and the processes thereof havebeen illustrated in the previous embodiment and are omitted herein.

Then referring to FIGS. 3E and 3F, wherein the FIG. 3F illustrates across-sectional view of the FIG. 3E along the line F-F′. A thin touchpanel 30 may further comprise a transparent over coat 46 covering thetransparent sensing layer 44, the transparent insulators 42, the metalconnecting structures 38 and the metal guiding lines 40 mentioned aboveand only conductive pads 48 for electrically connecting outside areexposed, so as to protect the above-mentioned structure from beingscraped except conductive pads 48. FIG. 3G illustrates an appliedexample of the present invention. Referring to FIG. 3G, a thin touchpanel 30 may be disposed on a display panel 50 to form a thin touchdisplay screen 60.

In summary, the black bordering, the sensing layer, the metal connectingstructures, the transparent insulators and the guiding lines of thepresent invention are directly formed on the inner surface of thetransparent substrate, thereby comprising the following benefits;

-   -   1. the transparent substrate not only capable of being a touch        end, but also having a touch control ability of thin touch panel        directly;    -   2. comparing to the conventional touch panel, the glass        substrate of the touch panel disposed between the cover lens and        the display panel in the present invention capable of being        simplified, so as to reduce material consumption and increase a        transparency of the touch panel;    -   3. in the steps of manufacturing the structure of the present        invention, the process of sticking the cover lens and the glass        substrate by using the optical adhesive capable of being left        out, so as to further reduce the cost of the sticking process        and enhance the yield rate; and    -   4. the thickness of the whole structure of the touch panel        capable of being reduced, so as to benefit a design tendency of        thinning out the product.

Although specific embodiments of the present invention have beendescribed, it will be understood by those of skill in the art that thereare other embodiments that are equivalent to the described embodiments.Accordingly, it is to be understood that the invention is not to belimited by the specific illustrated embodiments, but only by the scopeof the appended claims.

1. A thin touch panel, comprising: a transparent substrate, having anouter surface and an inner surface opposite to one another, said outersurface capable of being a touch end; a black bordering, formed on edgesof said inner surface to dispose around a sensing region; a plurality ofmetal connecting structures, arranged as an array and formed on saidsensing region, and a plurality of metal guiding lines formed on asurface of said black bordering; a plurality of transparent insulators,respectively corresponding to each of said metal connecting structures,and respectively covering part of said metal connecting structures, twoopposite ends of said metal connecting structures being exposed; atransparent sensing layer, comprising: a plurality of first sensingpads, arranged on said sensing region as an array; a plurality oftransparent conductive connecting structures, disposed across surfacesof said transparent insulators to electrically connect said firstsensing pads along a first direction; a plurality of second sensingpads, arranged on said sensing region as an array, and said secondsensing pads being electrically connected along a second direction byexposed said opposite ends of said metal connecting structures, saidsecond direction different to said first direction; and a plurality oftransparent guiding lines, formed on said metal guiding lines, andelectrically connected to part of said first sensing pads and part ofsaid second sensing pads; and a transparent over coat, covering saidsensing layer, said transparent insulators, said metal connectingstructures and said metal guiding lines.
 2. The thin touch panel asclaimed in claim 1, wherein said transparent substrate is a transparentinsulating board or a transparent insulating flexible board with amaterial of glass, polycarbonate (PC), polythylene terephthalate (PET),polymethylmethacrylate (PMMA), cyclic olefin copolymer (COC) orpolyether sulfone (PES).
 3. The thin touch panel as claimed in claim 1,wherein said black bordering is a black array pattern made of chromium(Cr), chromium oxide or resin.
 4. The thin touch panel as claimed inclaim 1, wherein said metal connecting structures and said metal guidinglines are made of a material comprising silver (Ag), chromium (Cr),aluminum (Al) or a molybdenum/aluminum/molybdenum (Mo/Al/Mo) stacklayer.
 5. The thin touch panel as claimed in claim 1, wherein a materialof said transparent insulators is PET.
 6. The thin touch panel asclaimed in claim 1, wherein said transparent sensing layer comprising amaterial of indium tin oxide (ITO), indium zinc oxide (IZO), antimonytin oxide (ATO), aluminum zinc oxide (AZO), zinc oxide (ZnO), tin oxide(SnO₂), or organic transparent conductive material.
 7. The thin touchpanel as claimed in claim 1, wherein a material of said transparent overcoat is silicon oxide (SiO₂) or PET.
 8. A thin touch panel, comprising:a transparent substrate, having an outer surface and an inner surfaceopposite to one another, said outer surface capable of being a touchend; a black bordering, formed on edges of said inner surface to disposearound a sensing region; a transparent sensing layer, comprising: aplurality of first sensing pads and a plurality of transparentconductive connecting structures, formed on said sensing region of saidinner surface, and said transparent conductive connecting structureselectrically connecting said first sensing pads along a first direction;a plurality of second sensing pads, formed on said sensing region, andisolated from one another and alternately arranged with said firstsensing pads; and a plurality of transparent guiding lines, formed on asurface of said black bordering, and electrically connected to part ofsaid first sensing pads and part of said second sensing pads; aplurality of transparent insulators, respectively covering each ofcorresponding said transparent conductive connecting structures, andeach of said transparent insulators crossing on two adjacent ends of twoisolated said second sensing pads; a plurality of metal connectingstructures, respectively formed on each of said transparent insulators,and electrically connecting said second sensing pads along a seconddirection, said second direction different to said first direction; aplurality of metal guiding lines, formed on said transparent guidinglines; and a transparent over coat, covering said sensing layer, saidtransparent insulators, said metal connecting structures and said metalguiding lines.
 9. The thin touch panel as claimed in claim 8, whereinsaid transparent substrate is a transparent insulating board or atransparent insulating flexible board with a material of glass, PC, PET,PMMA, COC or PES.
 10. The thin touch panel as claimed in claim 8,wherein said black bordering is a black array pattern made of Cr,chromium oxide or resin.
 11. The thin touch panel as claimed in claim 8,wherein said transparent sensing layer comprising a material of ITO,IZO, ATO, AZO, ZnO, SnO₂, or organic transparent conductive material.12. The thin touch panel as claimed in claim 8, wherein a material ofsaid transparent insulators is PET.
 13. The thin touch panel as claimedin claim 8, wherein said metal connecting structures and said metalguiding lines are made of a material comprising Ag, Cr, Al or a Mo/Al/Mostack layer.
 14. The thin touch panel as claimed in claim 8, wherein amaterial of said transparent over coat is SiO₂ or PET.